var app = angular.module('plunker', []);

app.controller('MainCtrl', function($scope) {
  $scope.name = 'World';
});
<!DOCTYPE html>
<html>

<head>
        <meta charset="utf-8" />
        <title>What is ngClick directive? Why we use it?</title>
        <script src="https://code.angularjs.org/1.4.1/angular.js"></script>
        <script>
                var app = angular.module('myApp', []);
                app.controller('ngClickCtrl', function($scope) {
                        $scope.firstName = "Anil";
                                $scope.lastName = "Singh";
                        $scope.IsActive = false;
                        $scope.AddName = function() {
                                $scope.IsActive = true;
                        };
                });
        </script>
</head>

<body ng-app="myApp">
        <h3>What is ngClick directive? Why we use it?</h3>
        <div ng-controller="ngClickCtrl">
                <div>
                        First Name:
                        <input type="text" ng-model="firstName"> Last Name:
                        <input type="text" ng-model="lastName">
                        <div ng-show="IsActive">
                                <h3>Full Name: {{firstName + " " + lastName}} </h3></div>
                </div>
                <div>
                        <button ng-click="AddName()">Display for ngClick FullName</button>
                        <br/>
                        <button ng-dblClick="AddName()">Display for ngDbClick FullName</button>
                        <br>
                        <button ng-mousedown="AddName()">ng-mousedown on this Button </button>
                        <br>
                </div>
        </div>
</body>

</html>
/* Put your css in here */